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Old Mar 29, 2022 | 10:28 AM
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Default Tranny fluid
Just got a 2020 ultra limited. Checked the tranny level and it didn’t have the familiar smell of 75w-90. It was serviced with syn3. For those running M8’s, are you sticking with the motor oil, or Harley’s (or equivalent) gear lube?
 
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Old Mar 29, 2022 | 10:35 AM
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Syn3 is a waste of money and designed with the **** people in mind. I use Redline shock proof in the trans, HD Formula + in the primary and HD 360 in the engine.

 
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Old Mar 29, 2022 | 10:37 AM
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They are not calling it that anymore.
 
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Old Mar 29, 2022 | 10:47 AM
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Oh oil thread! Nice!

My vote: Formula + in the Trans and Primary. Been using it for years without issue, and all the cool kids are doing it (like bath salts).
 
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Old Mar 29, 2022 | 11:14 AM
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I am asking seriously e cause I always ran redline in my ‘09, and HD now has and seems to promote their gear oil now. The bike had its first service before I bought it, and was surprised to not find their gear oil in it. I figured why offer it if it’s “not called for”.
 
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Old Mar 29, 2022 | 11:22 AM
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I just use wally worlds synthetic v twin 20-50 in all three holes. People way overthink lubricants.
 
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Old Mar 29, 2022 | 11:29 AM
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Originally Posted by propflux01
I am asking seriously e cause I always ran redline in my ‘09, and HD now has and seems to promote their gear oil now. The bike had its first service before I bought it, and was surprised to not find their gear oil in it. I figured why offer it if it’s “not called for”.
it's been around for nearly two decades now and always been factory fill for CVOs...seems they produced it so they could get in on the synthetic market and their piece of the $$ pie, and out of convenience and simplicity for folks that want to keep it simple using a 3 hole solution..the cynic in me thinks they only use it as factory fill for CVOs because it's their most expensive fluid and figure folks that can afford CVOs won't balk at using it regularly..the engines and transmissions in the non CVOs ain't any different and their conventional HD360 and Formula + have always worked just fine..matter of fact some foreign markets don't even specify SYN3 as factory fill for CVOs..I switched to their new 80W140 Syn gear oil over 20,000 miles ago after exclusively using Formula + for 15 years in our bikes which had several performance builds..I like the 80W140 in both trans and primary, but honestly if they never came out with synthetics at all the HD360 and Formula + would continue to perform and protect their powertrains adequately
 
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Old Mar 29, 2022 | 11:33 AM
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Originally Posted by lp
Oh oil thread! Nice!

My vote: Formula + in the Trans and Primary. Been using it for years without issue, and all the cool kids are doing it (like bath salts).
As usual, lp is on point.
 
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Old Mar 29, 2022 | 12:26 PM
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Originally Posted by 702
Syn3 is a waste of money and designed with the **** people in mind. I use Redline shock proof in the trans, HD Formula + in the primary and HD 360 in the engine.

I ran redline through one of my change internals, switched over to bel ray and have done two changes with bel ray since and there is still redline coming out during the changes. That $h!t is like Elmer’s glue mixed with pepto bismol! I’m not knocking redline, just saying it definitely hangs around awhile, LoL
 
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Old Mar 29, 2022 | 12:34 PM
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Originally Posted by Quik
I ran redline through one of my change internals, switched over to bel ray and have done two changes with bel ray since and there is still redline coming out during the changes. That $h!t is like Elmer’s glue mixed with pepto bismol! I’m not knocking redline, just saying it definitely hangs around awhile, LoL
And it actually shows on the dipstick
 
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